The present invention relates to a high speed screw feeder for shaped containers or bottles fashioned in glass or plastic material.
Conventional screw devices comprise a horizontally disposed feed screw, a belt by which containers conveyed along the feed screw are supported from beneath, and a stationary fence positioned on the side of the belt opposite from the screw, parallel with the screw axis.
Such devices are widely utilized in transferring bottles to labeling or rinsing stations, or other bottling plant equipment.
The fence serves to restrain and guide the bottles on the side farthest from the screw.
Whilst conventional devices of the type in question function well enough with the familiar container or bottle of cylindrical shape, narrowing at the neck, drawbacks are encountered in the case of containers or bottles differently embodied, such as those of oval section, of rectangular or square section with well defined corners, and especially, for example, in the case of bottles exhibiting a cross section appearing square with rounded corners substantially of "Dee" shape.
The irregular outline of such containers, in fact, prevents the device from operating at high speed as this leads to jamming caused by the shattering of bottles, in the case of glass, or as the result of plastic containers becoming flattened.
Such situations arise by reason of the fact that the non-cylindrical containers or bottles can enter the screw feeder in a diversity of positions, each theoretically requiring a corresponding adjustment of the device in order that the relative shape can be accommodated by the blade of the screw.
Accordingly, as the speed of rotation of the screw is increased, and the feed velocity of the bottles or containers thus raised, the problems associated with shape are multiplied.
Such is the case more especially with containers in plastic material, which are easily deformable.
The object of the present invention is to eliminate the drawbacks mentioned above, and in particular to provide a device by which containers or bottles of non-cylindrical or irregular shape can be conveyed at high speed without any risk of the screw being jammed by shattered glass or deformed plastics. It is a further object of the invention to ensure that containers are taken up and conveyed by the screw in such a way that each will exit from the device correctly positioned.